Originally posted on: http://geekswithblogs.net/ihaynes/archive/2013/08/07/microsoft-launches-windows-phone-app-studio.aspx
Microsoft have launched Windows Phone App Studio, an online browser based tool which allows users to create simple apps for Windows Phone 8, based on templates and drag and drop components. They recommend you test your apps on a real phone before publishing on the app store, and any developer can unlock and register a single phone to load up to two apps. If you are registered with the Dev Center you can unlock up to three phones and upload up to 10 apps on each.
There are tutorials
There's a special deal of a 12 month Dev Center account for $19 which runs until 26th August.
http://apps.windowsstore.com/default.htm
You can also modify the look and feel of the generated app and this post describes how.
http://dotnetbyexample.blogspot.nl/2013/08/modifying-look-and-feel-of-your.html